WordPress 2.9.2 was released earlier today. You can download it here. This fixes a problem that allows users that are logged in to view trash posts authored by other users.
Thomas Mackenzie alerted us to a problem where logged in users can peek at trashed posts belonging to other authors. If you have untrusted users signed up on your blog and sensitive posts in the trash, you should upgrade to 2.9.2. As always, you can visit the Tools->Upgrade menu to upgrade.
Thomas Mackenzie goes into much greater detail about the problem on his site. Check his site out for more info on why the 2.9.2 release was necessary.